/**
 * Copyright (c) 2008, Andrew Carter
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without modification, are 
 * permitted provided that the following conditions are met:
 * 
 * Redistributions of source code must retain the above copyright notice, this list of 
 * conditions and the following disclaimer. Redistributions in binary form must reproduce 
 * the above copyright notice, this list of conditions and the following disclaimer in 
 * the documentation and/or other materials provided with the distribution. Neither the 
 * name of Andrew Carter nor the names of contributors may be used to endorse or promote 
 * products derived from this software without specific prior written permission. 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
 * SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR 
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.acarter.jmejtree;

import java.awt.Point;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.dnd.DnDConstants;
import java.awt.dnd.DropTarget;
import java.awt.dnd.DropTargetContext;
import java.awt.dnd.DropTargetDragEvent;
import java.awt.dnd.DropTargetDropEvent;
import java.awt.dnd.DropTargetEvent;
import java.awt.dnd.DropTargetListener;

import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;

import com.jme.scene.Node;
import com.jme.scene.Spatial;

/**
 * @author Carter
 */
public abstract class JMEJTreeDropTarget implements DropTargetListener {

	/**  */
	protected DropTarget target;

	/**  */
	protected JMEJTree tree;

	/**
	 * @param tree
	 * @param bridge
	 */
	public JMEJTreeDropTarget(JMEJTree tree) {

		this.tree = tree;

		target = new DropTarget(tree, this);
	}

	/**
	 * Drop Event Handlers
	 */
	private TreeNode getNodeForEvent(DropTargetDragEvent dtde) {

		Point p = dtde.getLocation();
		DropTargetContext dtc = dtde.getDropTargetContext();

		JMEJTree tree = (JMEJTree) dtc.getComponent();
		TreePath path = tree.getClosestPathForLocation(p.x, p.y);

		Object object = path.getLastPathComponent();

		if(object instanceof Spatial)
			return new JMEJTreeNode((Spatial) object);

		return null;
	}

	/**
	 * 
	 */
	public void dragEnter(DropTargetDragEvent dtde) {

		TreeNode node = getNodeForEvent(dtde);

		if(node.isLeaf())
			dtde.rejectDrag();
		else {
			// start by supporting move operations
			dtde.acceptDrag(DnDConstants.ACTION_MOVE);
			//dtde.acceptDrag(dtde.getDropAction());
		}
	}

	/**
	 * 
	 */
	public void dragOver(DropTargetDragEvent dtde) {

		TreeNode node = getNodeForEvent(dtde);
		
		if((node == null) || (node.isLeaf()))
			dtde.rejectDrag();
		else {
			// start by supporting move operations
			dtde.acceptDrag(DnDConstants.ACTION_MOVE);
			//dtde.acceptDrag(dtde.getDropAction());
		}
	}

	/**
	 * 
	 */
	public void dragExit(DropTargetEvent dte) {

	}

	/**
	 * 
	 */
	public void dropActionChanged(DropTargetDragEvent dtde) {

	}

	/**
	 * 
	 */
	public void drop(DropTargetDropEvent dtde) {

		Point pt = dtde.getLocation();
		DropTargetContext dtc = dtde.getDropTargetContext();

		JMEJTree tree = (JMEJTree) dtc.getComponent();
		TreePath parentpath = tree.getClosestPathForLocation(pt.x, pt.y);

		Object parentObject = parentpath.getLastPathComponent();

		if(parentObject instanceof Node) {

			JMEJTreeNode parent = new JMEJTreeNode((Node) parentObject);

			if(parent.isLeaf()) {

				dtde.rejectDrop();
				return;
			}

			try {

				Transferable tr = dtde.getTransferable();
				DataFlavor[] flavors = tr.getTransferDataFlavors();

				for(int i = 0; i < flavors.length; i++) {

					if(tr.isDataFlavorSupported(flavors[i])) {

						dtde.acceptDrop(dtde.getDropAction());

						TreePath p = (TreePath) tr.getTransferData(flavors[i]);
						Object object = p.getLastPathComponent();
						
						if(object instanceof Spatial)
							doDrop(parentObject, object);
						
						dtde.dropComplete(true);
						return;
					}
				}

				dtde.rejectDrop();
			}
			catch(Exception e) {

				e.printStackTrace();
				dtde.rejectDrop();
			}
		}
	}
	
	protected abstract void doDrop(Object parentObject, Object object);
}
